P0206

Technical Summary

P0206 means Injector Circuit/Open - Cylinder 6. The PCM has identified electrical behavior in the cylinder 6 injector circuit that does not match the expected response when that injector is commanded. On most port- and direct-injection strategies the controller monitors the driver circuit for an open load, short, abnormal voltage, or abnormal current response. The code names the cylinder 6 injector circuit; it does not prove that the injector itself is defective.

Monitor strategy: the controller does not set this code simply because a component name appears in the diagnostic description. It evaluates Cylinder 6 fuel injector electrical control circuit under calibrated enabling conditions. Those conditions can include ignition state, engine speed, battery voltage, coolant temperature, electrical load, injector command, or other prerequisites. The exact thresholds and timers are manufacturer-specific. Freeze-frame should therefore be treated as evidence of when the monitor failed, not just a list of numbers.

Start with the complete vehicle context. Secondary DTCs can reveal whether the failure is isolated or shared. Several injector circuit faults appearing together suggest a common power feed, splice, relay, harness, or controller supply. Multiple module undervoltage and communication faults alongside P0562 point toward a system-wide power problem. Save this evidence before clearing codes or disconnecting the battery.

Visual inspection remains valuable when it is targeted. Inspect connectors for terminal tension, corrosion, water or oil intrusion, heat damage, broken locks, and evidence of previous probing. Follow harnesses through brackets, engine movement points, exhaust heat zones, battery trays, and recently repaired areas. On charging-system faults, inspect the mechanical generator drive as well as the cables. On injector faults, identify the exact cylinder before touching the connector.

Electrical testing should prove the circuit under load. A digital ohmmeter can show continuity through a nearly broken or corroded conductor that fails when current flows. Use voltage-drop testing, an appropriate load, and comparison with a known-good circuit when possible. When testing PCM-controlled loads, use tools that will not damage the driver. Current probes and oscilloscopes are especially useful for injector circuits because they can show the electrical load and driver response during actual operation.

Mechanical faults must be separated from electrical faults. A restricted injector can cause a cylinder misfire but does not by itself prove an injector circuit/open code. Likewise, a slipping generator belt or high-resistance cable can create low system voltage even if the generator itself is functional. Follow the evidence from the monitor: first establish whether the electrical command and feedback are correct, then test mechanical performance when the symptoms require it.

Before condemning a PCM, verify its power feeds and grounds under load, connector condition, controlled load, and the entire external circuit. A shorted injector can damage an injector driver, and a poor PCM ground can make the module report voltage that differs from the battery. Controller replacement should be supported by a failed driver/input test after all external causes have been eliminated.

Safety changes the diagnostic plan. A flashing MIL with an injector fault means catalyst-damaging misfire may be occurring; unnecessary driving should stop. Battery and charging tests involve high available current, rotating components, and the possibility of sparks near a battery. Direct-injection systems may add high fuel pressure and application-specific injector-driver hazards. Follow the manufacturer's disabling, depressurization, and test procedures.

Repair verification is more than clearing the MIL. Recreate the original operating condition, watch current and pending codes, and verify the live data that originally failed. For an injector circuit, the affected cylinder should show stable electrical command and the misfire counter should stop accumulating. For system-voltage faults, measured voltage and PCM-reported voltage should agree and remain adequate during the specified operating/load conditions.

Finally, confirm the emissions and engine-risk picture. An unresolved injector circuit can cause raw fuel or excess oxygen to reach the catalyst depending on how the cylinder is failing, while low system voltage can disrupt fuel, ignition, throttle, transmission, and emissions controls across the vehicle. A proof-based diagnosis protects both the repair budget and downstream components.